Walker was recruited into ELO after founding member Roy Wood quit the band and took cellist Hugh McDowell and horn player/keyboardist Bill Hunt with him and also joining at the time on bass was Mike de Albuquerque. Their new bandmates were singer/songwriter/guitarist/bandleader Jeff Lynne, drummer Bev Bevan, keyboardist Richard Tandy (who had previously played bass, but switched to keyboards), violinist Wilf Gibson and cellist Mike Edwards[3] and, at the time, Walker lived in a bachelor flat in the London suburb of Queen's Park.[2]
During his time in ELO, Walker played cello on two of their albums – ELO 2 and side two of On the Third Day – and he used a German-made cello with steel strings.[2] He also contributed cello to the single Showdown.
After leaving ELO, Walker joined the orchestra at the Royal Opera House in Covent Garden, London. He played cello on "Fool's Gold", a track on the album Thought Talk by the rock band Starry Eyed and Laughing[2]
Haines, Marc, Patrik Guttenbacher, and Alexander von Petersdorff. 2000. "Colin Walker, Cello". facethemusic.de, Fanclub of the Electric Light Orchestra and all related artists.